Carbureter.



J. C. ADAM. CARBURETER.

APPLICATION FILED MAR. 27,191]- Pate nted Sept. 25, 1917.

jgrZ H 1 FFTQ.

CARBURETER.

Application filed March 27, 1917.

T 0 all whom it may concern:

Be it known that I, JOHN Orrnrs'rm ADAM, a subject of the King of Great Britain, residing at 75 Highlever road, North Kensington, in the county of London, England, have invented certain new and useful Improvements in Carbureters, of which the following is a specification.

This invention relates to carburetors.

The object of the invention is to provide an iniproved'for'm of carbureter which is simple to manufacture and generally eflicient in operation.

According to this invention a carbureter comprises a movable choke device having a central space of cross sectional area varying along its axis within which a fuel et is arranged and having passages through it which are adapted to be uncovered or covered progressively as the choke device is moved relatively to the fuel jet and means for maintaining the number of said passages which are uncovered constant though the choke device is moved relatively to the jet. The movement of the choke device may also vary the amount of the mixture or air passing to the engine. The choke tube or member preferably comprises a number of annular plates arranged one above another, spaced apart'and of diiferent internal diameters, the fuel jet being arranged on the axis of the plates and the choke device thus formed being movable within a cylinder so that the passage through the plates can be varied by withdrawing the choke device more or less from the cylinder.

The choke device may be arranged to be moved automatically by the suction of the engine.

The invention .will be fully understood from the following description taken in connection with the accompanying drawings which illustrate by way of example, methods of carrying the invention into effect and in which Figure 1 is a sectional elevation of one Specification of Letters Patent.

Patented Sept. 25, 1917.

Serial No. 157,677.

carbureter constructed according to this in; vention.

Referring to Figs. 1, 2 and 3 the carbureter comprises a body 1 having two cylind'rical parts 2 and 3. Centrally arranged within the cylindrical part 2 is a fuel jet 4 which is fed with fuel through a pipe 5 leading from a float chamber 6. The float chamber 6 is only indicated diagrammatically as it may be of any suitable construction. The body of the float chamber may be formed or cast in one piece with the body 1 of the carburetor or it may be separate therefrom; An inlet for air is provided at? and an opening at 8 leads to the induction pipe. Slidable within the cylindrical part 3 is a cylindrical cup-shaped part or piston 9 and slidable within the cylindrical part 2 is a. sleeve 10. A number of annular plates 11 arefixed to the base of the part 9 by bolts 12, these plates being spaced apart by washers 18 surrounding the bolts 12 and placed between the plates 11. The heads of the bolts 12 abut against a ring 14 supporting the lowermost annular plate 11. The three or four uppermost plates 11 are preferably closer together than the lower ones. The external diameters of the plates 11 are all the same and the plates lit the sleeve 10 but can slide therein. The internal diameters of the plates 11 increase downward so as to leave a conical space surrounding the fuel jet 1. The plates 11 therefore form a movable conical choke device surrounding the fuel jet. The piston 9 and with it the choke device are moved by a crank or arm 15 pivoted at 16 and connected by a link 17 with the base of the part 9. The lower end of the link 17 is provided with a cross-piece or head 18 which is received by a cap 19 made in two parts and fixed by screws to the part 9. The top of thepart 3 is provided with a screwed cap 20 which is slotted to allow the crank 15 'to pass through it. The crank 15 is connected in any suitable manner to ahand-operated lever or other suitable operating device. The sleeve 10 is provided with pins 20 which project through slots 21 in the cylindrical part 2 and these pins are connected in any suitable manner with a hand or other operating device. The part 9 andthe sleeve 10 may be moved or operated by Bowden wires connected to a lever giving dual control by having movement in two planes, movement of the lever in one'plane serving to move the part 9 and movement in the other plane serving to move the sleeve 10. Such an arrangement is diagrammatically illustrated in dotted lines in Fig. 2. The crank 15 has an arm 15 attached to it, which arm is connected by a- Bowden wire 15 to the operating lever 15 The pins 20 on the part 10 are also connected by the horseshoe frame 20 and Bowden wire 20 to the lever 15 The lever 15 has a part 15* attached to it, which part has two grooves 15 and 15 at right angles in which slide blocks 15 and 15 to which blocks the ends of the Bowden wires 15 and 2 0 are attached respectively. The part 15 can be moved by the lever'15' in the direction of either of the grooves 15 and15 and accordingly either of the Bowden Wires can be operated as described. The connection of the Bowden wires to the operating lever 15 is only diagrammatically indicated as suitable arrangements are well known in connection with control of aeroplanes. The

arrangement just referred to is suitable foruse on aeroplanes. Apart from themechanism described no throttle valve need be provided. I The carbureter-operates asfollows With the parts in the position shown in Fig. 1 the supply of mixture to the engine is entirely cut oil. If the part 9 and with it the choke device are slightly raised air entering by the vinlet 7 together with fuel from the fuel jet passes between the plates 11 into the space22 and thence to the in duction pipe through the outlet 8. As the part 9 is raised an increasing number of the outer edges of the plates 11 are uncovered thereby providing a passage for'the mixture in area of cross-section. Atthe same time the choking eflect of the choke device is varied owing to the conical shape of the central space within the choke device. By moving the sleeve 10 with the choke device after the latter has been raised the throttling elfect canbe maintained constant though the choke device is moved relatively to the jet.

The carbureter may be arranged to operate automatically, as illustrated for example in Fig. 4. The cylindrical part 3 is closed by a screw cap 20 and holes 23 are provided in the part 9. With this arrangement the suction of the engine withdraws air from above the part or piston 9 through the holes 2 3 thereby causing the part 9 and with it the choke device to rise. A spring 9 may 'be provided for controlling the movement of the choke device. With the carbureter arranged to act automatically an independent throttle valve is provided.

Referring to Fig. 5, the carbureter therein shown comprises a body 2 1 having two cylin drical parts 25 and 26 within which slides a cylinder or sleeve 27. A choke. device comprising annular plates 11 and a cuponto the top of the sleeve 27 Three slots or openings 30 are provided in the sleeve 27. By rotating the crank 15 the choke device can be raised relatively to the sleeve 27 and thereby permit the passage of the mixture between the plates 11 and through the openings 30 to the space 31 and thence through the outlet8 to the induction pipe, while at the same time the choking elfect of the choke device on the fuel jet is varied.' If the sleeve 27 is raised by raising the part 28 without.

permitting rotation of the crank 15 relatively thereto the amount of overlap of the openings 30 with respect to the choke device remains constant because the choke device in this case moves with the sleeve, while the.

choking effect on the fuel jet is varied. The rotation of the crank 15'may be elfected by means of the arm 15*. The raising of the part 28 may be effected by the link 28 connected to the bell-crank lever 28 pivoted on the bracket 28 In the carbureter shown in'Fig. 6 the general arrangement is similarto that shown in Figs. 1 to 3 but the plates 11 of the choke 0 device are arranged so thattheir internal diameters decrease downward. The orifice of the fuel jet when the air supply is cut off stands nearthe center of the ring 32. In order that'the fuel may be cut off a plate 33 is arranged above the fuel jet being attached thereto by arms 3 1, this plate fitting the orifice 35 in the ring 32. The choke device is moved downward to allow the passage of air, the air passing between the plates 11 before being mixed with the fuel. The sleeve 36 corresponds to thesleevelO shown in Figs. 1 to 3. The choke member is connected to the part 9bylong bolts so as to allow a free passage for the mixture to the induction pipe. I I

Instead of constructing this form of car-. bureter with a sleeve corresponding to the sleeve 10in Figs. 1 and 2, it may be constructed with the choke-device and .part 9 movable within a sleeve such as, the sleeve 27 shown in Fig. 5. The form of carbureter shown in: Fig. 6 is particularly adapted for use on aeroplanes. I What I claim and desire to secure by Letters Patent of the United States is :v

1. A carbureter comprising a movable choke device having a central space of crosssectional area varying along its axis within which a fuel jet is arranged and having passages through it which are adapted to be jet and means for maintaining the number of said passages which are uncovered constant though the choke tube is moved relatively to the jet.

2. A carbureter having a choke device comprising a number of annular plates arranged one above another, spaced apart and of different internal diameters within which a fuel is arranged, the device being movable within a cylinder so that by Withdrawing it from the cylinder a passage of variable area of cross-section through the device is pro vided, and a sleeve interposed between the choke device and the said cylinder the movement of said sleeve serving to permit of the area of cross-section of the said passage being maintained constant though the choke device is moved relatively to the jet.

3. A earbureter comprising a fitting consisting of. two coaxial cylinders with an intermediate connecting portion adapted to be joined to an induction pipe, a fuel jet arranged within one cylinder and surrounded by a choke device movable in this cylinder and connected to a piston movable in the second cylinder, the choke device comprising a number of annular plates arranged one above another, spaced apart and of different internal diameters, the arrangement being such that as the choke device is Withdrawn from the cylinder within which it moves a passage of varying area of cross-section to the induction pipe is provided and the choking eflect on the fuel jet is varied and a sleeve interposed between the choke device and the second cylinder, the movement of said sleeve serving to permit of the area of cross-section of the said passage being maintained constant though the choke device is moved relatively to the jet.

4:. A ca-rbureter having a choke device comprising a number of annular plates arranged one above another,spaced apart and of different internal diameters within which afuel jet is arranged, a cylinder within which the choke device can move and a sleeve having openings through it interposed between the choke device and the cylinder, the arrangement being such that as the choke tube is withdrawn from the cylinder a passage of varying area of cross-section to the induction pipe is provided and the choking efiect on 'the fuel jet is varied while by moving the said sleeve the area of cross-section of the said passage may be maintained constant though the choke device 1s moved relatively to the jet.

JOHN CHRISTIE ADAM.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

